Spotify fans have been waiting for a long time to get the service in the United States. It’s incredibly popular in the UK and across Europe, but licensing restrictions with major US music labels have prevented an American launch. That hasn’t stopped Spotify from expanding into new markets, and according to Forbes, Facebook and Spotify have partnered to build a new music service that could be launched within weeks.

According to Forbes’ sources, the service is under testing, but it’s definitely real and definitely coming. When launched, Facebook users will see a Spotify icon on their news feed right next to the icons for events, photos, and pages. Users will be able to install the Spotify client on their desktop and play songs from the Spotify service and from their own music libraries directly through Facebook. The upcoming service will even include social features to allow users to share the songs they’re listening to with friends in real-time.

Unfortunately for American music fans, the service will only be available in countries where Spotify is already licensed to operate. That means that until licensing disputes with American labels are settled, it won’t be available in the US. Spotify has said that those negotiations are still in progress though, so presumably when they reach a deal, the service will be rolled out to American users as well.

Forbes cites “sources close to the deal” with the news, but Spotify executives refused to comment. They pointed out that Spotify already has Facebook integration in the form of Facebook Connect, which allows users to log in via Facebook and share the songs they’re listening to on their wall. This deal would take the integration to an entirely different level, giving Facebook a built-in cloud-based music service.

When and how the service will be launched is still a mystery, but one thing is clear: both companies stand to gain significantly from a partnership. Facebook’s 500 million users are an attractive target for Spotify, and a built-in music service could encourage more Facebook users to stay logged in at the site: presumably playing (and paying for) games, catching up with friends, and pulling in ad revenue.